For several months, Jodie Arnold wondered what exactly happened the night her sweet, fun cousin Denise Closs died. She knew she had been fatally shot, but she knew few details, and her imagination filled in the horrifying blanks.

Those details were spelled out in the criminal complaint against suspect Jake Thomas Patterson, 21, who is accused of killing Denise, 46, and her husband James, 56, so he could kidnap the couple’s 13-year-old daughter, Jayme.

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The specifics of the Oct. 15, 2018, crime at the Closs home in Barron, Wisconsin, were worse than she imagined. “I was not prepared,” Arnold tells PEOPLE.

Arnold had hoped that her cousin had died quickly — perhaps while sleeping. Instead, her heart broke when she read in the complaint that Denise and Jayme heard the fatal gunshot that killed James, compelling Denise to call 911. Then, while she and Jayme hid in the bathtub, Denise enveloped Jayme in a protective bear hug moments before her death.

According to the complaint, the suspect asked Denise to put duct tape on her daughter’s mouth. Then, he fatally shot Denise.

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“Denise’s last thoughts were probably, ‘My daughter is next,’” Arnold says. “It makes me so heartbroken. It just wrecks me…When somebody dies, it just feels a million times worse when their last thoughts are of utter despair and terror. I had been hoping it had happened so fast that it wasn’t time for her understand.”

The criminal complaint was released by Barron County Sheriff’s Office on Monday. All week, says Arnold, she hasn’t been able to stop thinking Denise’s death.

“I wanted to know. I had to know — to give myself some closure. Unfortunately, with some closure came a whole new level of terror for me as a mom,” she says.

Denise Closs

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As a mom, she feels her job is to protect her kids. To keep them safe.

“I lock my doors at night, but that’s not good enough if somebody wants in,” Arnold says. “She did everything she could. They were barricaded in the bathroom hiding.”

Like many parents, Arnold says, she would lay down her life protecting her kids — but her cousin’s death shows that even if both parents die protecting their child, it still doesn’t necessarily keep them safe.

“Yes, I will die for my kids, but then you realize that doesn’t mean my kids are going to be okay,” she says. “When you’re in your house, you do feel safe. That guy had a mission and there was nothing stopping that….Mothers everywhere, are feeling extra protective of their kids.”

Patterson is being held in the Barron County Jail. He is charged with two counts of first-degree homicide, one count of kidnapping and one count of armed burglary, according to the complaint.

Jake Thomas Patterson

Barron County Sheriff's Dept

“This is a very tragic situation,” Patterson’s lawyers said in a joint statement, according to local media reports. “There is a substantial amount of information, interest, and emotion involved in this case. Mr. Patterson’s legal team will be relying on the integrity of our judicial system to ensure that everyone’s rights are protected and respected.”

Arnold watched the news footage of Patterson’s court appearance Monday, during which he was not asked to enter a plea. “That was hard — just to see this guy,” she says. “You feel like it’s happening all over again.”